If, like me, you have seen the film "The End of the Line?", you may be feeling thoroughly confused about fish. I used to love shopping for fish - all those shiny rows of delicious and fragrant things, poised beautifully on their bed of ice- but now I find myself standing in front of the fishmonger's counter and staring at it, totally baffled. For any one who cares about sustainability, all certainties seem swept away - so many of our most familiar and most delicious fish are endangered now, or farmed in vaguely disgusting conditions.
But there's always the lowly mackerel. They really are plentiful - I remember only a few years ago the children pulling their rods out of the sea near Teignmouth with five or six mackerel squiggling on the multiple hooks every time, and that hasn't changed. No one has yet suggested that there's any scarcity.
In cooking and eating terms, though, mackerel's a bit of a problem. It's an uncompromising taste, and it doesn't lend itself to many recipes. Very fresh and simply pan-fried, perhaps rolled in oats, and eaten with a squeeze of lemon, mackerel is great - but that's about it. Other ways of cooking it seem hard to come by. Here's one, though, that is a bit more unexpected. It's mackerel that is cured and pressed, rather than actually cooked, by the same method that makes gravadlax of salmon. It's eaten cold, so it's a perfect starter or lunch dish, but it's chunky enough to serve as a main course with potatoes, salad, whatever.
As with any cured fish, you need to be sure it's really fresh. That's not so hard with mackerel - it smells quite strongly even when first caught, so if your nose tells you it is a little overwhelming, it's not good enough.
Get fillets, with the skin on. Start the day before, or the morning before a dinner, as it takes a while to marinate in the curing mixture.
For six:
Six mackerel fillets
3 heaped tablespoons sea salt
3 heaped tablespoons granulated sugar
1 heaped tablespoon green peppercorns
2 bunches dill
All you do is to grind the peppercorns roughly, and mix them with the salt, the sugar and the dill roughly chopped, stalks and all. There's so much oil in the fish that you don't need anything else.
Line a low dish with cling film, and put a layer of curing mixture in the bottom. Lay the fillets, skin side down, on top, then put another layer of mixture over them, rubbing it well in. Wrap the whole lot up in the cling film.
Now find a way of putting weight on top of your packet of fish, to press it down quite hard. A board that fits inside the dish would be perfect: put a pile of cookbooks on top of the board, if you have't any old-fashioned weights. Now put the dish in a cool place for anything between 12-24 hours (longer is better), and once or twice turn over the packet of fillets and pour off the oil that will have accumulated in the bottom of the dish.
When you're ready to eat, take the fillets out of the marinade and rinse them in cold water to get rid of excess salt - and then go for it. Lime is nicer than lemon, if you want to squeeze something on them - but the ideal thing is a mustard/dill sauce or a very nippy dill mayo. I often cheat by taking a good shop-bought mayo and tarting it up with a bit of plain yogurt, lots of chopped dill, a spoon of grainy mustard and a big squeeze of lemon.